Add missing documentation for S.S.Cryptography (dotnet#4892)

* Add missing documentation for S.S.Cryptography

* Apply feedback

Author: bartonjs

xml/System.Security.Cryptography.Pkcs/ContentInfo.xml

@@ -283,14 +283,12 @@
         <Parameter Name="encodedMessage" Type="System.Byte[]" />
       </Parameters>
       <Docs>
-        <param name="encodedMessage">An array of byte values that represents the encoded <see cref="T:System.Security.Cryptography.Pkcs.ContentInfo" /> message from which to retrieve the outer content type.</param>
-        <summary>The <see cref="M:System.Security.Cryptography.Pkcs.ContentInfo.GetContentType(System.Byte[])" /> static method  retrieves the outer content type of the encoded <see cref="T:System.Security.Cryptography.Pkcs.ContentInfo" /> message represented by an array of byte values.</summary>
-        <returns>If the method succeeds, the method returns an <see cref="T:System.Security.Cryptography.Oid" /> object that contains the outer content type of the specified encoded <see cref="T:System.Security.Cryptography.Pkcs.ContentInfo" /> message.  
-  
- If the method fails, it throws an exception.</returns>
+        <param name="encodedMessage">An array of byte values that represents the encoded CMS ContentInfo message from which to retrieve the outer content type.</param>
+        <summary>Retrieves the outer content type of an encoded CMS ContentInfo message.</summary>
+        <returns>The outer content type of the specified encoded CMS ContentInfo message.</returns>
         <remarks>To be added.</remarks>
-        <exception cref="T:System.ArgumentNullException">A null reference  was passed to a method that does not accept it as a valid argument.</exception>
-        <exception cref="T:System.Security.Cryptography.CryptographicException">An error occurred during a cryptographic operation.</exception>
+        <exception cref="T:System.ArgumentNullException"><paramref name="encodedMessage" /> is <see langword="null" />.</exception>
+        <exception cref="T:System.Security.Cryptography.CryptographicException"><paramref name="encodedMessage" /> cannot be decoded as a valid CMS ContentInfo value.</exception>
       </Docs>
     </Member>
     <Member MemberName="GetContentType">
@@ -312,10 +310,11 @@
         <Parameter Name="encodedMessage" Type="System.ReadOnlySpan&lt;System.Byte&gt;" Index="0" FrameworkAlternate="dotnet-plat-ext-5.0;net-5.0" />
       </Parameters>
       <Docs>
-        <param name="encodedMessage">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="encodedMessage">A read-only span of byte values that represents the encoded CMS ContentInfo message from which to retrieve the outer content type.</param>
+        <summary>Retrieves the outer content type of an encoded CMS ContentInfo message.</summary>
+        <returns>The outer content type of the specified encoded CMS ContentInfo message.</returns>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.Security.Cryptography.CryptographicException"><paramref name="encodedMessage" /> cannot be decoded as a valid CMS ContentInfo value.</exception>
       </Docs>
     </Member>
   </Members>

xml/System.Security.Cryptography.Pkcs/SignedCms.xml

@@ -844,8 +844,8 @@ The following permissions are required to access the signature key:
         <Parameter Name="encodedMessage" Type="System.Byte[]" />
       </Parameters>
       <Docs>
-        <param name="encodedMessage">Array of byte values that represents the encoded CMS/PKCS #7 message to be decoded.</param>
-        <summary>The <see cref="M:System.Security.Cryptography.Pkcs.SignedCms.Decode(System.Byte[])" /> method decodes an encoded <see cref="T:System.Security.Cryptography.Pkcs.SignedCms" /> message. Upon successful decoding, the decoded information can be retrieved from the properties of the <see cref="T:System.Security.Cryptography.Pkcs.SignedCms" /> object.</summary>
+        <param name="encodedMessage">An array of byte values that represents the encoded CMS/PKCS#7 message to be decoded.</param>
+        <summary>Decodes an encoded <see cref="T:System.Security.Cryptography.Pkcs.SignedCms" /> message.</summary>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
@@ -867,8 +867,8 @@ The following permissions are required to access the signature key:
   
  ]]></format>
         </remarks>
-        <exception cref="T:System.ArgumentNullException">A null reference was passed to a method that does not accept it as a valid argument.</exception>
-        <exception cref="T:System.Security.Cryptography.CryptographicException">A cryptographic operation could not be completed.</exception>
+        <exception cref="T:System.ArgumentNullException"><paramref name="encodedMessage" /> is <see langword="null" />.</exception>
+        <exception cref="T:System.Security.Cryptography.CryptographicException"><paramref name="encodedMessage" /> could not be decoded successfully.</exception>
         <altmember cref="M:System.Security.Cryptography.Pkcs.SignedCms.Encode" />
       </Docs>
     </Member>
@@ -891,9 +891,12 @@ The following permissions are required to access the signature key:
         <Parameter Name="encodedMessage" Type="System.ReadOnlySpan&lt;System.Byte&gt;" Index="0" FrameworkAlternate="dotnet-plat-ext-5.0;net-5.0" />
       </Parameters>
       <Docs>
-        <param name="encodedMessage">To be added.</param>
         <summary>To be added.</summary>
+        <param name="encodedMessage">A read-only span of byte values that represents the encoded CMS/PKCS#7 message to be decoded.</param>
+        <summary>Decodes an encoded <see cref="T:System.Security.Cryptography.Pkcs.SignedCms" /> message.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.Security.Cryptography.CryptographicException"><paramref name="encodedMessage" /> could not be decoded successfully.</exception>
+        <altmember cref="M:System.Security.Cryptography.Pkcs.SignedCms.Encode" />
       </Docs>
     </Member>
     <Member MemberName="Detached">

xml/System.Security.Cryptography.X509Certificates/X509Certificate2.xml

@@ -819,11 +819,28 @@
         <Parameter Name="keyStorageFlags" Type="System.Security.Cryptography.X509Certificates.X509KeyStorageFlags" Index="2" FrameworkAlternate="net-5.0" />
       </Parameters>
       <Docs>
-        <param name="fileName">To be added.</param>
-        <param name="password">To be added.</param>
-        <param name="keyStorageFlags">To be added.</param>
-        <summary>To be added.</summary>
-        <remarks>To be added.</remarks>
+        <param name="fileName">The name of a certificate file.</param>
+        <param name="password">The password required to access the X.509 certificate data.</param>
+        <param name="keyStorageFlags">A bitwise combination of the enumeration values that control where and how to import the certificate.</param>
+        <summary>Initializes a new instance of the <see cref="T:System.Security.Cryptography.X509Certificates.X509Certificate2" /> class using a certificate file name, a password, and a key storage flag.</summary>
+        <remarks>
+          <format type="text/markdown"><![CDATA[  
+  
+## Remarks  
+> [!IMPORTANT]
+>  Never hard code a password within your source code.  Hard-coded passwords can be retrieved from an assembly using the [Ildasm.exe (IL Disassembler)](/dotnet/framework/tools/ildasm-exe-il-disassembler), a hex editor, or by simply opening up the assembly in a text editor such as Notepad.exe.  
+  
+If you create an <xref:System.Security.Cryptography.X509Certificates.X509Certificate2> certificate by specifying a PKCS7 signed file store for `fileName`, the <xref:System.Security.Cryptography.X509Certificates.X509Certificate2> is created for the certificate that signed the store rather than for any of the certificates within the store.  
+  
+ ]]></format>
+        </remarks>
+        <exception cref="T:System.Security.Cryptography.CryptographicException">An error with the certificate occurs. For example:  
+  
+-   The certificate file does not exist.  
+  
+-   The certificate is invalid.  
+  
+-   The certificate's password is incorrect.</exception>
       </Docs>
     </Member>
     <Member MemberName=".ctor">

xml/System.Security.Cryptography.X509Certificates/X509SubjectKeyIdentifierExtension.xml

@@ -168,9 +168,10 @@
         <Parameter Name="critical" Type="System.Boolean" Index="1" FrameworkAlternate="net-5.0" />
       </Parameters>
       <Docs>
-        <param name="subjectKeyIdentifier">To be added.</param>
-        <param name="critical">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="subjectKeyIdentifier">A read-only span of bytes that represents data to use to create the extension.</param>
+        <param name="critical">
+          <see langword="true" /> if the extension is critical; otherwise, <see langword="false" />.</param>
+        <summary>Initializes a new instance of the <see cref="T:System.Security.Cryptography.X509Certificates.X509SubjectKeyIdentifierExtension" /> class using a read-only span of bytes and a value that identifies whether the extension is critical.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>